Temperature control systems such as HVACs, water heaters, boilers, etc., typically include a blower impeller that is configured to create a movement of air (herein ‘air flow’) therethrough. For example, a temperature control system may include a forced draft fan that is configured to force air into the temperature control system to provide air for combustion or an induced draft fan that is configured to extract the air from the temperature control system through the heat exchangers post combustion and exhaust the air through a venting duct (vent) that may be coupled to the temperature control system. A change in air flow in the temperature control system due to a blockage in the vents, a blower impeller malfunction, etc., may create unstable, unsafe, and inefficient operating conditions in the temperature control system.
Conventional temperature control systems use pressure switches to detect said change in the air flow and responsively shut down the operation of the temperature control system when there is a threshold change in air flow to prevent any damage to the temperature control system and/or related consequences. For example, as illustrated in FIG. 1, an example water heater 100 may include three pressure switches (106, 108, and 112). Two of the pressure switches (106, 108) are disposed in the air intake vent 102 and the exhaust vent 104, respectively, and are used to detect vent blockage in the air intake vent 102 and the exhaust vent 104; while the third pressure switch 112 is disposed after the blower impeller 110 and before the heat exchanger 114 and is used to detect the presence and proper operation of the blower impeller 110. The pressure switches (106, 108, and 112) may be set to open and responsively shut down the water heater or end a heating cycle of the water heater when a specific threshold pressure for which the pressure switches (106, 108, and 112) are set is reached due to the change in airflow resulting from a vent blockage or blower impeller malfunction. Each time a temperature control system is shut down, it takes several minutes to recover and re-start the temperature control system which may be inconvenient and may negatively affect the efficiency of the temperature control system.
The pressure switches are not configured to detect and/or provide a warning regarding a condition of the temperature control system that is not critical, but causes inefficient operation and could lead to a shutdown of the temperature control system if the condition is left unaddressed. In other words, the pressure switches are not configured to warn a user regarding a condition that could lead to a shut down and provide the user an opportunity to address the condition, prevent the shutdown of the temperature control system, and/or to operate the temperature control system at a higher efficiency. Further, the pressure switches may add to the number of components and the cost of the temperature control system. Furthermore, the pressure switches may occupy space and inhibit a compact design of the temperature control system. For example, as illustrated in FIG. 1, the pressure switches (106, 108, and 112) may be attached external to the water heater using harnesses and may include pressure sensing tubes extending external to and from the side of the water heater, thereby preventing a compact design of the water heater.
It is noted that this background information is provided to reveal information believed by the applicant to be of possible relevance to the present disclosure. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present disclosure.